Synthesis and Electrochemical Properties of TiO2 /Carbon Composites by Microwave Process

Much attention is focused on electrochemical capacitors (ECs) due to its potential use in high power energy storage devices. Electrode materials studied widely for ECs are carbon, conducting polymers, and transition metal oxides. Various carbon forms are used as support of metal or metal oxide. The composite electrodes show a combined effect of the electrochemical double layer capacitance (EDLC) and the pseudocapacitance related to faradaic redox reactions. TiO2 was reported to reduce the polarization of the electrode of EDLC due to its hydrophilic property and can be considered to be a promising electrode material due to its high electrochemical performance, abundance, and environmentally benign nature. The high conductivity of carbon nanotube (CNT) and the high ion transfer through the CNT can give good effect on the capacitance of the composite electrode. A solid precipitation method employing microwave heating process could be developed to prepare metal oxide/carbon composites. In this study, we report on the synthesis of TiO2/carbon and TiO2/CNT nanocomposite using microwave-assisted heating process. Physical and chemical properties of the synthesized materials were characterized by transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), N2 sorption analysis (BET surface area). Their electrochemical activities were measured using three electrode system in 1 M of Na2SO4 solution by means of cyclic voltammetry (CV), galvanostatic charge/discharge, and electrochemical impedance spectroscopy (EIS). Detailed synthetic procedure, electrochemical and structural properties of TiO2/carbon and TiO2/CNT nanocomposites will be presented at the meeting in terms of nucleation and growth of metal oxide nanoparticles, and specific capacitance of the nanocomposites.